Processes of facilitating and controlling chemical reactions or physical treatments



Aug. 7, 1945. G. D. DILL 2,381,119

PROCESSES OF FACILITATING AND CONTROLLING CHEMICAL REACTIONS OR PHYSICAL TREATMENTS Filed June 20, 1940 INVENTOR 6/455/27' 0 flu;

ATTORNEYS tans m mainstay divided solid; or "a a iinely divldjed solid and'a fluid,

and incursion treatments, or -.fine'l y' divided solidsfdimculty is, in bringing about such an i-s'itherl the oi" the two-; 'solid s'ojfbetween the particles" of particles of'the acid; that the desired; and speed '0! reaction orioiphysical'tre'atlncnt'can be obtained, or .even a de dably reaction or physical-treatment.=

The present invention mismatched-owes an mrmv d, v rmmhl eflech ing,- in; predetermined and controlled manner, such "a1 thorough and interaction, either of divided Isolldsw'ith each other or of. a'iluid-and a iinely divided solld or of two fluids with each othen'that rapid,feflective Y properly controlled ichemicalreactions or physi-' cal treatments, and particularly in which finely divided 's'oiids' are involved, may be brought about without waste oi. energygor of materials. The invention relates-particularly to the facilitation and control oi. chemical reactions or-physical treatments in which a gas era-vapor is employed in a dual treatment.

Among thechemlcal reactions or physical out ments, to the facilitation and control otwhich the present invention lendsitself, are. reduction reactions. eitherot the type in which finely divided ores are reduced by means oi tlnelydivided solidreducing agents, such as carbonQoroi thetype in. which the reduction of the. ilneiydivided ores is? eii'ected by meansoi fluidr'educinalasents, such inwhicnone orniore finely .di-videdsolids'a're' involved:

pacity in the rel flotl'orphysical treatment'and an important objector the invention'is the directionand controlof the gas or its plurality 'ot i I n1 reference to the hereinabove aivenillustrainents to the facilitation and control or which the tlon, therefore, is to produce sucha controlled and directed state of turbulence in the gas or vapor employedin the reaction or treatment that;

7 application to the facilitation and control of recapacity'in the reaction or physicalv jcreasedvelocity and reduced pressure and of reduced velocity and increased pressure to produce as carbon monoxide gas; hydro'ien or hydrocarbons, catalytic processesinxwhich the 'catalystis in a iineiy divided state.- partial reduction processes, such as those sometimes employed as'steps in ore beneiiciatina processes, impregnation proccases, such; for example, processes or impregnating iinely divided ores with'carbon preparatory,

to reduction, and gas reforming processes; Other chemical reactions and'pll'ysical'treatmentsfto the ia ci1itationand control" oi" which the invention chemical'i or" physical treatments in I be primarily either a reagent, or ameans' doraction,1or a carrier for a reaaentorror "some". a material-used in eiiectins a physical .treatment,.-'

' ments, will insure such commingling and interaction oithe solid particles with the fluid partides and with each other as to insure a rapid,

" preierablyeither a gas or a vapor, which is to the desirediturbulence, the iinely divided solid v-th'erein thus created.

he themselves to 1 ashe'reinaboveuugaesteitheinvention relates thev tadlitation; and control or which a g'aszo'r, a vapor is" employed in a dual 'ca vapor to perform tive. list-o1- chemical reactions and physical treatinvention lends itself, it will be seen that the gas orva'por'takins'part in the reaction or treatment producing a physclal condition tavor'in'a there-.

etc. An important object of the present invenin addition to periormins its primary function, the gas'or vapor, by entraining the particles oi a finely divided solid with it inits turbulent moveeiiective and. readily controlled chemical reaction or physical treatment.

An important teature oi the invention. in its actlonsor physical treatments in which finely I divided solids are involved, is the utilization of meansior so confining and directing the-fluid,

participate in the reaction or other treatment involvinsv-aufinely divided solid,'that the fluid moves-upwardly under a substantially constant iiowdmpelling pressure and in its upward travel is iorced through sharply contrasted zones of inbeing'introduced into this fluid stream in such manner that it will oi the turbulence "The invention contemplates introducing the finely divided solid into the fluid stream either sothat its overall travel is in the same direction as the fluid stream or so that its overall travel .is counter-to the direction of flow of the fluid stream. The invention further contemplates recycling a portion oi the fluid stream, and of any of the solid particles entrained therein, from the zone of high pressure and low velocity again through the zone of low pressure and high velocity further to insure the desired commingling and interaction of the solid particles and the fluid particles with each other.

Further to insure a thorough commingling and interaction of the fluid and. the solid particleswith each other, the invention contemplates so baiiiing the fluid stream, and particularly in the vicinity of the point of its' discharge froni the zone of high velocity and low pressure into the zone of low velocity and high pressure, as to contribute still more to the turbulent efl'ect. An important feature of the invention is the use of a streamlined baiile to aid in securing a selective action, particularly when recycling, an important feature of the invention, as a whole, being its capacity for s classifying the materials being acted upon, during their passage through the apparatus, that those requiring more extended treatment will receive it.

Although, as hereinabove suggested, this invention has especial utility in the facilitation and control of chemical reactions and physical treatments in which finely-divided solids are involved it is also useful for insuring a thorough commingling and interaction of two fluids, either two gases, two liquids, a gas and a liquid or agas and a vapor as, for example, in the reformation, by means of steam, or a hydrocarbon containing gas into a substantially hydrocarbon free as having, as its principal constituents, hydrogen and carbon monoxide.

One of the flelds in which the novel process of the present invention have found particular utility is in the fleld of catalytic reactions in which intimate and prolonged contact between a gas or vapor and a powdered catalyst at an elevated temperature is desired.

Where a powdered solid is contacted with a liquid or vapor, for example in catalytically cracking petroleum hydrocarbons, it is difficult to keep the mixture of powdered solid and liquid or vapor homogeneous due to the difference in gravity and the tendency of the solid toseparate from the liquid or vapor. This is especially true when the powdered solid catalyst and the liquid or vapor are introduced together into a reaction chamber. In

such case the solid usually tends to separate from the liquid or vapor and thereby the total beneflcial effect of the catalytic solid is not obtained.

A particular object of the invention, therefore, is to provide a reaction chamber wherein a definite volume of powdered catalyst will be intimatelycontacted with a definite volume of the vapor for a deflnite period of time. A further object of the invention is to provide means for insuring recirculation of portions of the vapor and the powdered catalyst.

- Other objects and important features of the invention will appear from the following description and claim, when considered in connection with the accomp yin drawing, in which two forms of apparatus for practicing the novel process of the present invention are illustrated, thi application as to common subject-matter being in parts continuation of my co-pendins application Serial No. 244,612, filed December 8, 1938.

Figure 1 is a diagrammatic sectional view of apparatus suitable, for practice of the novel process of, the present inventipn;

Figure 2 is a section on the line 2-2 of Figure 1;

Figure 3 is a section on the line 3-4 0! HI- v ure 1.

In the form of the invention shown in min;

1 to 3 inclusive, the chamber or chambers in which the reaction or physical treatment is to take place, hereinafter referred to as "reaction" chambers, may be enclosed within a cylindrical side wall 2 and top and bottom walls 4 and j. To conserve heat, when the heat for the or physical treatment is supplied by preheating the substances taking part in the reaction or physical treatment, the entire casing may be enclosed within an insulating covering I. It will, of course, be understood thatt in some cases, instead or supplying the entire'fheat for the reaction or physical treatment by preheating the substances or elements taking part therein, the easing in which the reaction chamber, or chambers, is located may be heated in any other suitable manner. 1

The fluid which is to take part in the reaction and/or physical treatment within the reaction chamber or chambers, or which is to entrain the elements or substances which are to react or take part in the physical treatment, is introduced into the lower end of the lower reaction chamber. two chambers being shown. The conduit for the fluid comprises a straight section of tubing II to the upper end of which is connected one section I! of a venturi, the section I! having a comparatively steeply tapering interior passage is to produce the desired increase in velocity and reduction in pressure of the inflowing fluid.

At its upper end the interior passage in the section I! terminates in a cylindrical throat II.

The outer [face II of the upper end of the section I2 is also conical and tapers to meet the interior passage in a comparatively sharp me II, the tapered upper end of the section II ex tending through the bottom of an inverted frusto-conical partition or bafile II in the casing I, which forms the bottom of the reaction chamber 2| and serves as a hopper-like structure to direct the fluid and any entrained solid to be recirculated to the low pressure part of the venturi, more fully to be described hereinafter. Positioned above the upper end of the section II of the venturi is a section 22 in which is formed the expansion end of the venturi, the section 22 having at its lower end a bellmouthed opening 24 of an internal conical taper substantially corresponding to the external conical taper of the outer face u of the sectim II andbeingspacedfromthetaperedupperendof the section I: sufliciently to provide an annular passage 2' from the reaction chamber 2| into the passage through the venturi sectim 22. The conical or bell-mouthed lower end ll of the passage through the section 22 of the Ventm-l structure connects at its upper end with the sapansion part II of the venturi which, at its upper end, discharges into the reaction chamber 'II.

From the foregoing description, it will be seen that a fluid entering the pipe II and flowing under a substantially uniform flow-impelling pressure will, as it is forced through the cm:- tracting passage If in the section II, travel. under the well-known law of the flow of fluids, at an increased velocity but at a reduced pressure through the throat I at the upper end of the passage l3 and will be Droiected into the bell mouth 24 in'the section 22 at this increased velocity. Although the bell mouth 24 is slightly larger in diameter than the throat ll, there will be no substantial opportunity for expansion of section i2 and the inner wall of the'bell mouth 2i communicates, thus creating a suction tending to drawthe'surrounding fluid into this passage for recirculation together with any flnely divided solids that may be entrained in the fluid.

Where the conical upper end of the section i2 1 projects through the bottom opening in. the frusto-conical partition or home 2', the flt of the conical end of the section 12 within the opening is preferably a fluid-tight fit and, if desired, these parts may be permanently connected together. -At it v outer edges the-frustoconical partition member or baiiie le flts tightly within the-cylindrical casing member 2 and may,

if desired be permanently secured thereto or may be bodily removable therefrom. Asherein shown, the partition member 2| is preferably connected to spacer bars ll received in marginal recesses in the outer edge of the member 2|,

these spacer bars ll being also connected to a second partition member 32 of the-same general construction as the partition member 2.. Connected to the partition member I2 and extending through an opening-in the bottom thereof --in the same manner as the venturi section 12 is the venturi section 34 which cooperates with aventuri section It located above the partition member 32 in the same manner as the venturi section II cooperates with the venturi section 22 of the lower chamber 2i.

Located above the expansion ends of'the re- Y spective venturis are baiiies II and 40 which are preferably stream-linedin shape, the balls ll being supported by three brace members 4! connected at their upper ends to the baiile and at their lower ends to the inner face of the partition member 2| and the baiiie being supported by similarbrace members connected thereto and to the partition member .32 in the same manner. The venturi sections 22 and It are also shown as supported in'their proper relations to the sections i2 and SI, respectively, by connections to the respective sets of brace members 42 and II.

It will be obvious from the foregoing description that, if desired, the lower partition member 2ll might constitute the lower end-of the casing, since the space in the'casing 2 bounded by the partition-member 20 and the end wall 6 serves no functional purpose in the operation of the device. Asshown, the partition members 2| and 32 and the'end'wall l deflne, withthe cylindrical casing wall 2, two reaction or treatment chambers 2| and 4t.

Having regard to the foregoing description of the apparatus; it will be seen that, when employed to facilitate and control a reaction between av powdered catalytic solid and a fluid, such for example as petroleum oil vapor, and the catalytic solid, entrained in the oil vapor, i introduced into.

ingly. It will, nevertheless, emerge from the venturi at a considerable velocity as compared with its overall rate of travel through the chamber 2| of comparatively large diameter.

As the mixture of vapor and powdered catalytic solid, which has been speeded up in the restricted passage of the venturi, emerges from the venturi, it strikes the egg-shaped or stream-lined baiiie 88, which is preferably so spaced from the discharge end of the venturi that the greater part of the stream of mixed catalyst and fluid is deflected toward the inner walls of the casing 2 of the chamber II. The sudden expansion of the fluid as it emerges from the venturi, coupled with the impact of the mixed stream of fluid and solid against the blunt end of the balls 38, produces considerable turbulence which tends to keep the solid particles entrained in the fluid, but the slowing up of the rate of travel or the stream through the enlarged part of its conduit constituted by the chamber 2i reduces the entraining effect somewhat, especially near the surrounding wall 2. The particles of solid, therefore, which have not been carried on by the stream directly into the upper venturi, together with the more slowly moving parts of the stream against the outer wall 2 tend to be drawn downwardly by the partial vacuum at the opening 2! into the venturi -i 2 and in this way enter the venturi to be recirculated, the solid par-.-

ticles which are not still entrained sliding down the hopper-like inner face of the partition 2| to be picked up or entrained again by the fluid as it I is drawn into the annular opening" between the venturi sections i2 and 22, V

The streamlining of the baflle It tends, by reason-oi the-fact that the axi of the streamlined baiiie is in alignment with the entrance into the venturi section .34. to direct some of the fluid emerging from the lower venturi directly into the upper venturi together with the solid particles entrained therein. This action will be cumulative so that eventually all of the solid parti'cleaineluding those which have been recirculated, will enter the upper chamber 46 through theupper venturi. As the mixture which travels through the upper venturi emerges therefrom, it strikes the similar baiiie 4. in chamber and a part of it is deflected outwardly to be re-circulated and a part travels on into the upper discharge passage II in a tube II connected to the upper end i of the reaction chamber ll. The operation which takes place in chamber is substantially. the

same as that which took place in the-lower chamber 2i, the overall result being that a thorough commingling and interaction of the fluid, such as petroleum vapor, ,andthe powdered solid, such as g a catalyst to react therewith, is brought about.

Although two reaction or treatment chambers 2i and 48' are shown as provided in the casing 2, it willbe understood that the numberrmay be more or less according as it is found necessary or desirable to eflect-amore or less extensive commingiihg and interaction of thematerials which are taking part in the reactionor physical treat- A's hereinabove suggested, numerous other uses for theapparatus herein shown will readily occur to those skilled in the arts.

set forth in my co-pending application Serial No. 335,763, filed May 1'7, 1940, now Patent No. 2,288,613 of July "I, 1942. In such case the form of theapparatus shown in Figures 1 to'3 would be used to effect the coating and/or impregnation For example, the apparatus herein shown could be used in succession in the reduction of metallic oxides, as more fully from, gradually increasing the velocity of the stream of gases and solids during the initial portion of the path of said gases through said restricted passages, thereafter gradually reducing the velocity of the gas stream during its passage through the final portion of said restricted passages and reintroducing solids separated from said gas stream in said enlarged zones into said gas stream while said gases are passing at maximum velocity through said restricted passages to thereby redisperse the solids so separated into said gas stream.

GILBERT D. DILL. 

